Cookie stuffing involves placing an affiliate tracking cookie on a website visitor's computer without their knowledge, which will then generate revenue for the person doing the cookie stuffing. This not only generates fraudulent affiliate sales but also has the potential to overwrite other affiliates' cookies, essentially stealing their legitimately earned commissions.
I concluded that having read a product review, people felt more informed to make a purchasing decision. As a result, if they did click a link after reading the review they were more likely to buy the product. Those clicking on the top link seemed to be more in a ‘surfing’ mode. They clicked on the link less because they wanted to buy it but more out of interest to learn more. Some bought the product and some bought other products once they were ‘in the door’ at Amazon.